Airflow control system in refrigerators and freezers

ABSTRACT

An airflow control system in refrigerators and freezers, which comprise: a refrigerating compartment ( 10 ; an air cooling compartment ( 20 ) lodging an ( 21 ) and a fan ( 22 ); and an air distributing plenum ( 23 ), receiving a forced airflow from the fan ( 22 ) and having a front wall ( 24 ) provided with air passages ( 25 ) through which the forced airflow is supplied to the interior of the refrigerating compartment ( 10 ), at least part of the air passages ( 25 ) provided in the front wall ( 25 ) of the air distributing plenum (23) being operatively associated with respective closing means ( 40 ), which are selectively displaced to different operative positions, in which they maintain the air passages ( 25 ) with a free area dimensioned as a function of the intensity of the forced airflow to

FIELD OF THE INVENTION

The present invention refers to a system to provide the selective control of the airflows that are forced to circulate in the interior of determined regions of the refrigerating and freezing compartments defined in a refrigerating cabinet. The invention is applied to refrigerators and freezers with the cabinet presenting a single compartment, or multiple compartments, each frontally closed by a door.

PRIOR ART

In the refrigerators and freezers with forced ventilation, which are combined or not, a cool airflow is supplied to the different compartments by air passages provided in a front wall of an air distributing plenum usually located in the rear region of each respective compartment and which receives a forced cool airflow coming from an air cooling compartment, in which an evaporator and a fan are lodged.

FIGS. 1 and 2 of the enclosed drawings schematically illustrate a refrigerating compartment 10, in whose rear region is formed an air cooling compartment 20 lodging an evaporator 21 and a fan 22. The fan 22 produces an airflow which is forced to flow from the air cooling compartment 20 to an air distributing plenum 23, disposed in front of the air cooling compartment 20 and which presents a front wall 24, facing the refrigerating compartment 10 and provided with a plurality of air passages 25 which allow the cool air, which is insufflated into the air distributing plenum, to be distributed to different levels in said refrigerating compartment 10, in order to refrigerate the load contained in the latter.

The construction exemplified in FIGS. 1 and 2 is generally applied to the freezing compartment of a combined cabinet which is inferiorly provided with a refrigerating compartment (not illustrated), in whose rear region is installed a cool air distributing duct provided with air passages in its front wall facing said refrigerating compartment, and said air distributing duct being superiorly connected to the air distributing plenum 23, so as to receive from the latter a cool airflow to be distributed to different levels of the refrigerating compartment.

The air passages 25 provided in the air distributing plenum 23, or in the air distributing duct of the refrigerating compartment, are arranged and dimensioned to allow the respective compartment to have its load homogenously refrigerated or frozen. However, the physical distribution and the dimensioning of said air passages 25 cannot be altered, consisting in a passive system which will always produce the same refrigerating or freezing effect, independently of the operative specifications desired by the user operating said compartment.

These prior art solutions do not allow the user to adjust the refrigerating intensity of different regions selected in one or another compartment, according to the characteristics of the load to be refrigerated or frozen in said region. When the user desires to modify the conditions in a region of one of the compartments, this modification generally involves changing the operational ranges of the refrigerating system, proportionally influencing the temperatures in the other regions of one or more compartments.

OBJECTS OF THE INVENTION

By reason of the limitations related to the operational versatilities imposed by the cool air distributing systems of refrigerators and freezers, it is a generic object of the present invention to provide a system which allows controlling or adjusting the forced cool airflow in predetermined different regions of a refrigerating compartment, defined by a freezing or a refrigerating compartment in a refrigerating cabinet, without said selective control affecting the characteristics of a forced cool air supplied to the other regions of the refrigerating compartments provided with said control system.

SUMMARY OF THE INVENTION

In order to allow a refrigerator or a freezer of the type considered herein to operate according to the above-mentioned object, the present control system has at least part of the air passages provided in the front wall of the air distributing plenum operatively associated with respective closing means, which are selectively displaced to different operative positions, in which they maintain said air passages with a free area that is dimensioned as a function of the intensity of the forced airflow to be supplied to the refrigerating compartment.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described below, with reference to the enclosed drawings, given by way of example only and in which:

FIG. 1 is a simplified schematic vertical sectional view of a refrigerating compartment provided with a system for supplying a forced cool airflow, constructed according to the prior art;

FIG. 2 is a front view of the refrigerating compartment illustrated in FIG. 1, with the respective door being opened for visualizing the arrangement of the air passages that supply the airflow refrigerated in said refrigerating compartment;

FIG. 3 is a vertical sectional view of the refrigerating compartment illustrated in FIG. 1, but provided with the system for controlling the forced cool airflow of the present invention; and

FIGS. 4-8 are simplified and schematic front views of the refrigerating compartment illustrated in FIGS. 1 and 2, but provided with the system for controlling the forced cool airflow of the present invention, in different operative conditions.

DETAILED DESCRIPTION OF THE INVENTION

As illustrated in the drawings and commented in the introduction of the present specification, the invention is related to refrigerating appliances, such as refrigerators or freezers, combined or not and which are provided with forced ventilation.

As previously mentioned, the invention aims at providing a refrigerating compartment 10, which can take the form of a freezing compartment or a refrigerating compartment, with a system which allows for the selective control of the refrigerating intensity produced in predetermined different regions of said refrigerating compartment which are served by respective air passages 25 provided in the front wall 24 of the air distributing plenum 23, positioned in the rear region of the refrigerating compartment 10 and which is supplied with a forced cool airflow coming from an air cooling compartment 20, disposed immediately behind the air distributing plenum 23 or spaced from the latter, said air cooling compartment 20 lodging an evaporator 21 and a fan 22, which is responsible for supplying an airflow refrigerated by the evaporator 21 to the inside of the air distributing plenum 23.

According to the present invention, at least some of the air passages 25 are operatively associated with respective closing means 40, preferably interconnected to each other and which are selectively displaced between different operative positions, in which they produce different closing conditions of said air passages 25. In a first operative position, as illustrated in FIG. 7, the closing means 40 assume a position in which the free area of the respective air passages 25 allows the forced cool airflow, which is supplied in the respective regions of the refrigerating compartment 10, to be the project nominal airflow which produces a refrigerating degree considered-normal for the refrigerating appliance.

In a second operative position, as illustrated in FIG. 8, the closing means 40 are displaced to at least one position, in which they allow the respective air passages 25 to present a free area larger than that defined in the first operative position. It should be understood herein that the second operative position can be defined in a point that corresponds to the total opening of the respective air passages 25 (see FIG. 8), or subdivided in different second operative positions (not illustrated), in which the free area of the air passages 25 presents different values higher than that corresponding to the first operative position. In any of the second operative positions, an increase of the forced cool airflow is obtained in the respective regions of the refrigerating compartment 10, increasing the refrigerating or freezing velocity of the load in said region. Each second operative position of the closing means 40 can be used to help the operation in a fast-freezing position, increasing the refrigerating efficiency in said region, in case the refrigerating compartment 10 is a freezing compartment.

The closing means 40 can be further selectively displaced to at least one third position, in which they promote the reduction of the free area of the respective air passages 25. Thus, the airflow is reduced or eliminated in the respective regions of the refrigerating compartment 10, causing an increase in its operational temperature. This function can be used to preserve ice creams, which for consumption require a higher temperature than those temperatures obtained inside a freezing compartment in the refrigerating appliances of the no-frost type. FIGS. 4, 5 and 6 illustrate third positions for the closing means, with the respective air passages 25 being fully closed.

In the condition of FIG. 5, some of the air passages 25 are partially open, while in FIG. 6 they are open.

By having its temperature thus controlled, the refrigerating compartment 10 can be closed, i.e., separated from the remainder of the compartment of the refrigerating appliance, or opened to the interior of said compartment. By providing a refrigerating compartment 10 which is closed in relation to the rest of the compartment, the efficiency of the refrigerating appliance is increased.

The closing means 40 can be constructed in different manners, so as to be manually or automatically driven by means of a function selector 50 which is operatively associated with the usual control module (not illustrated) provided in the refrigerating appliances considered herein.

In a possible construction, the closing means 40 can take the form of plate portions formed as a single assembly, simultaneously operating against the air passages 25 and being driven by a driving means 60, which can take the form of a solenoid or an electric motor, which is automatically driven as a function of the operational characteristics adjusted by the user in the function selector 50 to which the driving means is operatively associated.

In the illustrated construction, the closing means 40 takes the form of a plate which is internally and parallely displaced to the front wall 24 of the distributing plenum 23, superiorly and inferiorly seated on rails 27 provided on an internal face of said front wall 24. It should be understood that other closing forms are perfectly possible, whose operation need not be performed by linear displacement. The closing means is/are able to be configured in such a way as to present an angular displacement around the axis which is orthogonal or parallel to the front wall 24 of the air distributing plenum 23.

The present control system can be further used to provide the full closing of the air passages 25 during the defrost operation of the refrigerating appliance, as illustrated in FIG. 4, preventing the heat generated by the defrost resistance from passing to the refrigerating compartment 10 through said air passages, reducing the increase of the temperature in the load, which generally occurs during the periodic defrost of the appliance. In this case, the closure of the air passages is automatically instructed to the function selector 50 by the command module of the refrigerating appliance, without the user having to interfere.

It should be further understood that the front wall 24 of the air distributing plenum 23 can be provided with air passages 25 presenting the same cross section area, but whose free area will be defined by the operative position of the respective closing means 40. In another constructive form, corresponding to that shown in the drawings, the front wall 24 of the air distributing plenum 23 is provided with air passages with different cross section areas. 

1. An airflow control system in refrigerators and freezers, which comprise: a refrigerating compartment (10; an air cooling compartment (20) lodging an evaporator (21) and a fan (22); and an air distributing plenum (23), receiving a forced airflow from the fan (22), and having a front wall (24) provided with air passages (25) through which the forced airflow is supplied to the interior of the refrigerating compartment (10), characterized in that at least part of the air passages (25) provided in the front wall (25) of the air distributing plenum (23) is operatively associated with respective closing means (40) which are operatively displaced to different operative positions, in which they maintain the air passages (25) with a free area dimensioned as a function of the intensity of the forced airflow to be supplied to the refrigerating compartment (10).
 2. The system as set forth in claim 1, characterized in that the closing means (40) are automatically displaced to the different operative positions by a respective driving means (60), which is operatively associated with a function selector (50) operated by the user.
 3. The system as set forth in claim 2, characterized in that the driving means (60) is defined by a solenoid.
 4. The system as set forth in claim 2, characterized in that the driving means (60) is defined by an electric motor.
 5. The system as set forth in claim 1, characterized in that the closing means (40) are defined by respective plate portions, which are displaced internally and parallely to the front wall (24) of the air distributing plenum (23).
 6. The system as set forth in claim 5, characterized in that the plate portions of the closing means (40) are formed in a single plate, which is displaced, superiorly and inferiorly, seated on rails (27) provided in the front wall (24) of the air distributing plenum (23).
 7. The system as set forth in claim 1, characterized in that the closing means (40) are selectively displaced to a first operative position, in which they maintain the respective air passages (25) with a free area dimensioned to supply the refrigerating compartment (10) with a project nominal forced airflow; at least one second operative position, in which they maintain the air passages (25) with a free area larger than that of the first operative position; and at least a third operative position, in which they maintain the air passages (25) with a free area smaller than that of the first operative position.
 8. The system as set forth in claim 7, characterized in that the closing means (40) present different third positions, one of which completely blocking the respective air passages (25), and different second operative positions, one of which providing to said air passages (25) the largest free area thereof.
 9. The system as set forth in claim 7, characterized in that the front wall (24) of the air distributing plenum (23) is provided with air passages (25) not associated with closing means (40) and presenting a free area dimensioned to supply the refrigerating compartment (10) with a project nominal forced airflow equal to that supplied by the other air passages (25) when the closing means (40) are in the first operative position.
 10. The system as set forth in claim 9, characterized in that the closing means (40) are automatically displaced to an operative position, in which they completely block the respective air passages (25) and the other air passages (25) when the refrigerating compartment is submitted to a defrost operation. 